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检查是否支持分区:
show plugins;
如果显示有
partition ACTIVE,则表示是支持分区
分区类型：
范围(range)：通过指定的列中的值作为区间范围
列表(list):与range相似,区别是匹配一个指定的列值
哈希(hash):是基于用户定义的函数对列的值计算后返回结果决定保存在哪一个分区中
键值(key):与hash类似，基于一个或多个列来评估，并且由mysql服务器提供函数
===============================
基于 range,其中的rang中结果值为 整型
as:
CREATE TABLE members (
firstname VARCHAR(25) NOT NULL,
lastname VARCHAR(25) NOT NULL,
username VARCHAR(16) NOT NULL,
email VARCHAR(35),
joined DATE NOT NULL
)
PARTITION BY RANGE( YEAR(joined) ) (
PARTITION p0 VALUES LESS THAN (1960),
PARTITION p1 VALUES LESS THAN (1970),
PARTITION p2 VALUES LESS THAN (1980),
PARTITION p3 VALUES LESS THAN (1990),
PARTITION p4 VALUES LESS THAN MAXVALUE
);
或者：
CREATE TABLE employees (
id INT NOT NULL,
fname VARCHAR(30),
lname VARCHAR(30),
hired DATE NOT NULL DEFAULT ‘1970-01-01‘,
separated DATE NOT NULL DEFAULT ‘9999-12-31‘,
job_code INT NOT NULL,
store_id INT NOT NULL
)
PARTITION BY RANGE (store_id) (
PARTITION p0 VALUES LESS THAN (6),
PARTITION p1 VALUES LESS THAN (11),
PARTITION p2 VALUES LESS THAN (16),
PARTITION p3 VALUES LESS THAN MAXVALUE
);
////////////////////////////////////////////
基于 list:(list列表结果为整型)
与range类似，主要区别在于，list(表达式)中的表达式值为指定的一组具体值(即枚举值),
并且list中的值一定要在分区中，并且分区中的结果为整型:
as:
CREATE TABLE employees (
id INT NOT NULL,
fname VARCHAR(30),
lname VARCHAR(30),
hired DATE NOT NULL DEFAULT ‘1970-01-01‘,
separated DATE NOT NULL DEFAULT ‘9999-12-31‘,
job_code INT,
store_id INT
)
PARTITION BY LIST(store_id) (
PARTITION pNorth VALUES IN (3,5,6,9,17),
PARTITION pEast VALUES IN (1,2,10,11,19,20),
PARTITION pWest VALUES IN (4,12,13,14,18),
PARTITION pCentral VALUES IN (7,8,15,16)
);
///////////////////////////
基于 range columns:(列的类型可为 string,date,datetime)
与range类似，但范围列不接受表达式，只接收列名称
范围列是基于比较元组(列表值)而不是标量之间比较
格式如下：
CREATE TABLE table_name
PARTITIONED BY RANGE COLUMNS(column_list) (
PARTITION partition_name VALUES LESS THAN (value_list)[,
PARTITION partition_name VALUES LESS THAN (value_list)][,
...]
)
column_list:
column_name[, column_name][, ...]
value_list:
value[, value][, ...]
--------------------
as:
create table rcx(
a int,
b int,
c char(3),
d int
)
partition by range columns(a,b,c)(
partition p0 values less than (4,2,10),
partition p1 values less than (10,20,‘mmm‘),
partition p2 values less than (maxvalue,maxvalue,maxvalue)
)
------------------
as:
CREATE TABLE employees_by_lname (
id INT NOT NULL,
fname VARCHAR(30),
lname VARCHAR(30),
hired DATE NOT NULL DEFAULT ‘1970-01-01‘,
separated DATE NOT NULL DEFAULT ‘9999-12-31‘,
job_code INT NOT NULL,
store_id INT NOT NULL
)
PARTITION BY RANGE COLUMNS (lname) (
PARTITION p0 VALUES LESS THAN (‘g‘),
PARTITION p1 VALUES LESS THAN (‘m‘),
PARTITION p2 VALUES LESS THAN (‘t‘),
PARTITION p3 VALUES LESS THAN (MAXVALUE)
);
////////////////////
基于list columns:(表达式中值的类型为:string,date,datetime)
as:
CREATE TABLE customers_1 (
first_name VARCHAR(25),
last_name VARCHAR(25),
street_1 VARCHAR(30),
street_2 VARCHAR(30),
city VARCHAR(15),
renewal DATE
)
PARTITION BY LIST COLUMNS(city) (
PARTITION pRegion_1 VALUES IN(‘Oskarshamn‘, ‘Högsby‘, ‘Mönsterås‘),
PARTITION pRegion_2 VALUES IN(‘Vimmerby‘, ‘Hultsfred‘, ‘Västervik‘),
PARTITION pRegion_3 VALUES IN(‘Nässjö‘, ‘Eksjö‘, ‘Vetlanda‘),
PARTITION pRegion_4 VALUES IN(‘Uppvidinge‘, ‘Alvesta‘, ‘Växjo‘)
);
---------------------------
CREATE TABLE customers_2 (
first_name VARCHAR(25),
last_name VARCHAR(25),
street_1 VARCHAR(30),
street_2 VARCHAR(30),
city VARCHAR(15),
renewal DATE
)
PARTITION BY LIST COLUMNS(renewal) (
PARTITION pWeek_1 VALUES IN(‘2010-02-01‘, ‘2010-02-02‘, ‘2010-02-03‘,
‘2010-02-04‘, ‘2010-02-05‘, ‘2010-02-06‘, ‘2010-02-07‘),
PARTITION pWeek_2 VALUES IN(‘2010-02-08‘, ‘2010-02-09‘, ‘2010-02-10‘,
‘2010-02-11‘, ‘2010-02-12‘, ‘2010-02-13‘, ‘2010-02-14‘),
PARTITION pWeek_3 VALUES IN(‘2010-02-15‘, ‘2010-02-16‘, ‘2010-02-17‘,
‘2010-02-18‘, ‘2010-02-19‘, ‘2010-02-20‘, ‘2010-02-21‘),
PARTITION pWeek_4 VALUES IN(‘2010-02-22‘, ‘2010-02-23‘, ‘2010-02-24‘,
‘2010-02-25‘, ‘2010-02-26‘, ‘2010-02-27‘, ‘2010-02-28‘)
);
以上可以用 range columns代替：
CREATE TABLE customers_3 (
first_name VARCHAR(25),
last_name VARCHAR(25),
street_1 VARCHAR(30),
street_2 VARCHAR(30),
city VARCHAR(15),
renewal DATE
)
PARTITION BY RANGE COLUMNS(renewal) (
PARTITION pWeek_1 VALUES LESS THAN(‘2010-02-09‘),
PARTITION pWeek_2 VALUES LESS THAN(‘2010-02-15‘),
PARTITION pWeek_3 VALUES LESS THAN(‘2010-02-22‘),
PARTITION pWeek_4 VALUES LESS THAN(‘2010-03-01‘)
);
///////////////////////
hash分区：
主要用于保证预定数量分区间数据分布均匀，hash返回的类型为整数,
用取模方法分区，即 (hash结果mod)/分区数)
as:
CREATE TABLE employees (
id INT NOT NULL,
fname VARCHAR(30),
lname VARCHAR(30),
hired DATE NOT NULL DEFAULT ‘1970-01-01‘,
separated DATE NOT NULL DEFAULT ‘9999-12-31‘,
job_code INT,
store_id INT
)
PARTITION BY HASH(store_id)
PARTITIONS 4;
此时，store_id会被4整除,此时相当于分区为 0,1,2,3,即余数,
默认时用1开始，即分区 1,2,3,4,当值为0时，在1区，值为1时，在2区,...
as:
CREATE TABLE employees (
id INT NOT NULL,
fname VARCHAR(30),
lname VARCHAR(30),
hired DATE NOT NULL DEFAULT ‘1970-01-01‘,
separated DATE NOT NULL DEFAULT ‘9999-12-31‘,
job_code INT,
store_id INT
)
PARTITION BY HASH( YEAR(hired) )
PARTITIONS 4;
////////////////
线性hash(linear hash):
与 普通hash类似，不同之处是用了 linera hash,还有就是分区算法用的是(线性的2的幂的运算法则)
CREATE TABLE employees (
id INT NOT NULL,
fname VARCHAR(30),
lname VARCHAR(30),
hired DATE NOT NULL DEFAULT ‘1970-01-01‘,
separated DATE NOT NULL DEFAULT ‘9999-12-31‘,
job_code INT,
store_id INT
)
PARTITION BY LINEAR HASH( YEAR(hired) )
PARTITIONS 4;
////////////////
key分区：
与hash类似，但是不允许用用户自定义的表达式，可以不用手动指定分区键，
默认会选择使用主键/唯一键作为分区键，没有主键/唯一键，则要指定分区键,
key的使用类似 hash
as:
CREATE TABLE k1 (
id INT NOT NULL PRIMARY KEY,
name VARCHAR(20)
)
PARTITION BY KEY()
PARTITIONS 2;
------------------
as:
CREATE TABLE tm1 (
s1 CHAR(32) PRIMARY KEY
)
PARTITION BY KEY(s1)
PARTITIONS 10;
---------------------
其实如 hash一样，可以使用 linear key,
as:
CREATE TABLE tk (
col1 INT NOT NULL,
col2 CHAR(5),
col3 DATE
)
PARTITION BY LINEAR KEY (col1)
PARTITIONS 3;
////////////////////
子分区：是在每一个分区进一步划分。
CREATE TABLE ts (id INT, purchased DATE)
PARTITION BY RANGE( YEAR(purchased) )
SUBPARTITION BY HASH( TO_DAYS(purchased) )
SUBPARTITIONS 2 (
PARTITION p0 VALUES LESS THAN (1990),
PARTITION p1 VALUES LESS THAN (2000),
PARTITION p2 VALUES LESS THAN MAXVALUE
);
以上实现就有6个分区了
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原文地址：http://www.cnblogs.com/lin3615/p/4767556.html
